Key featuresISL6328A
Dual 2A/1.7A High Efficiency Synchronous Buck Regulators with Up to 97% Efficiency and Low IQ (40μA)
180° phase output reduces ripple current and EMI
Prebiased output start-up prevents negative current output stage
Forced PWM mode and PFM mode can be selected
External synchronization rises to 8MHz
Negative current detection and protection
100% maximum duty cycle minimum voltage drop
Internal current mode compensation
Peak current limit, hiccup mode short-circuit protection and overtemperature protection
Pb-free (RoHS compliant)
AEC-Q100 certified components
description
The ISL78322 is a high efficiency, dual output synchronous step-down DC/DC regulator that provides up to 2A/1.7A continuous output per channel. The channel is
Input RMS current and EMI reduction with 180° phase. The 2.8V to 5.5V supply voltage range allows the use of a single Li+ cell, three NiMH cells, or a regulated 5V input. Current-mode control architecture that operates at high frequencies with very low duty cycles with fast transient response and excellent loop stability. The ISL78322 operates at a 2.25MHz switching frequency, allowing the use of small, low-cost, inductors and capacitors. Each channel is optimized to generate output voltages as low as 0.6V. The ISL78322 has a user-configurable operating mode, forced PWM mode and PFM/PWM mode. Forced PWM mode reduces noise and RF interference, while PFM mode provides the highest efficiency by reducing switching losses at light loads. In PFM operation, the total quiescent current plotted by the two channels is only 40μA, resulting in high light load efficiency and extended battery life. The ISL78322 provides a 1ms Power Good (PG) signal to monitor both outputs at power-up. When powered off, the ISL78322 discharges the output capacitor. Other features include internal digital soft-start to sequence the power supply, overcurrent protection, and thermal shutdown. The ISL78322 is available in a 4mmx3mm, 1mm, maximum height 12-lead DFN package. The complete converter occupies less than 1.8 cm 2 zone. The ISL78322 is qualified for AECQ100 and is specified for operation in an ambient temperature range of -40°C to +105°C (Class 2).